Accidents with wild animals, particularly relatively large wild animals such as deer, stags or wild boar, are regretfully part of the daily road scene and not only usually end in the death of the wild animals in question but also cause high levels of annual personal and material damage. Ever quieter vehicles, which also have a tendency to move at a higher speed, mean that the trend toward serious wildlife accidents has rather increased in recent years, since the animals are not left with sufficient time to escape when a vehicle approaches. Wildlife accidents are not just a large problem for road traffic, however, but are also a large source of danger for rail traffic, particularly for high-speed passenger trains, and also for aircraft that are taking off and landing.
Particularly for road traffic, a wide variety of approaches to preventing wildlife accidents have been developed in past decades. Besides costly structural measures, such as creating wildlife bridges, wildlife tunnels or wildlife fences, a wide variety of wildlife warning devices are also known that are usually fitted at the edge of the road on exposed road sections and are intended to prevent collisions between wild animals and vehicles by transmitting audible and/or visual signals. A variant of such wildlife warning devices is based on the detection of the wild animals themselves. By way of example, wildlife warning devices are known that use light barriers that run along the roadsides, with interruption of the light barrier by a wild animal being followed by the transmission of audible and visual warning signals in order to prevent the wild animal from crossing the road. Other wildlife warning devices are based on the detection of approaching vehicles. Such apparatuses are known as passive and active variants. The passive variants merely involve the headlamp light from approaching vehicles being deflected to the side by suitable reflectors, as a result of which the visual effect is meant to prevent the wildlife from crossing the road and hence to avoid accidents. The effectiveness of such passive reflectors is found to be very restricted, however. Much more effective are active electronic wildlife warning devices that have a dedicated electric power supply and, by way of example, use a light sensor to detect an approaching vehicle and are subsequently able to actively emit audible and/or visual warning signals. A typical example of such a wildlife warning device that has an electric power supply, at least one signal generator for emitting audible and/or visual signals and a microcontroller for controlling the signal generator is the wildlife protection appliance from the applicant, which is sold under the name WWG2.1 and is one of the most effective commercially available appliances.
The patent specification US 2003071735 A1 describes a wildlife protection system (wildlife warning system) that can be activated by means of a radio signal, or that transmits an activation signal to adjacent wildlife warning systems upon activation by means of a sensor.
However, the electronic wildlife warning devices known to date are also associated with problems.
Appliances that involve the detection of the headlamp light from approaching vehicles have a relatively short early warning time for the wild animals, for example, when the vehicles are approaching at relatively high speed. Vehicle speeds of just approximately 50 km/h and above often do not leave the wild animals enough time to be able to leave the road before the vehicle arrives, however.
Furthermore, such appliances are ineffective in daylight, since the signal generators are triggered when a headlamp light is detected, which means that the appliances are usually activated by an ambient light sensor only at twilight or at the onset of night.
In the case of wildlife warning devices that, regardless of the amount of vehicles, are activated when the wild animals themselves are detected, there is also the risk of familiarization effects, since the triggering of the light and sound signals is then not associated with a specific danger situation. Therefore, the effectiveness of such installations can be impaired over the longer term.
Electronic wildlife warning appliances are generally also at risk of theft and complex to maintain on account of the limited life of the components. Therefore, frequent time-consuming and costly inspections are required in order to ensure continuous operation and availability of the wildlife warning devices.
The present invention is therefore based on the technical problem of providing a wildlife warning system that solves or at least minimizes the problems described above for known wildlife warning devices.